<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .tb {
            width: 500px;
            height: 300px;
            border: 1px solid #000;

            /*边框合并 默认值separate*/
            border-collapse: collapse;
        }

        .tb td {
            border: 1px solid #000;
            /*水平对齐 left center right */
            text-align: center;

            /*垂直对齐方式 注意 vertical-align只适用于表格   top middle bottom*/
            vertical-align: middle;
        }

         .tb th {
             border: 1px solid #000;
         }
    </style>
</head>

<body>


    <table class="tb">

        <tr>
            <th>1</th>
            <th>2</th>
            <!--单元格水平合并 注意把多余的删掉-->
            <th colspan="2">3</th>
            <th>5</th>

        </tr>
        <tr>
            <td>1</td>
            <td>2</td>
            <td>3</td>
            <td>4</td>
            <!--垂直合并 注意把多余的删掉-->
            <td rowspan="2">5</td>

        </tr>
        <tr>
            <td>1</td>
            <td>2</td>
            <td>3</td>
            <td>4</td>
        </tr>
        <tr>
            <td>1</td>
            <td>2</td>
            <td>3</td>
            <td>4</td>
            <td>5</td>

        </tr>



    </table>



</body>

</html>